Effectiveness of Vaccination Against COVID-19 in Brazil: Case-Control Study

The main objective of the study is to evaluate the effectiveness of the vaccine against covid-19, recommended by the national immunization program. This is a multicentric, observational, case-control study. Participants Cases with the disease will be compared to Control Participants, that is, without the disease, regarding the vaccination history for Covid-19.Complementarily, an evaluation of cellular and humoral immunity will be carried out in a sample of both case and control participants, taking into account the vaccination history.

Inclusion Criteria:Agreement to participate in the study after reading, understanding and signing the informed consent.Availability and possibility of being followed up during the follow-up period defined in the study, through visits to research centers, home visits, telephone contacts or other means of digital communication.Completing the case or control definitions described below.Exclusion Criteria:Behavioral, cognitive or psychiatric illness that, in the opinion of the responsible investigator or his/her medical representative, affects the participant's ability to understand and comply with the requirements of the study protocol;Any other condition that, in the opinion of the responsible investigator or his/her medical representative, may jeopardize the safety or rights of a potential participant or prevent him/her from complying with this protocol.